As Decode Mandarin Chinese’s article on the suffix 子[^1] pointed out this suffix (zi2) is quite versatile and can append to many different kinds of words to ‘nounify’ them. This article is written with Mandarin in mind, so I’ve only plunked out the ones I think are relevant to Cantonese, ones that we would more likely to encounter as Cantonese speakers here.

The first usage is adding to verbs to make nouns for whatever’s doing the action.

VerbNoun
(pin3)
to deceive
騙子(pin3 zi2)
liar
(taam3)
to search / scout
探子(taam3 zi2)
scout

The second usage is adding to monosyllabic nouns to turn them into a two syllable nouns. This is certainly much more commonly done in writing than in speech to, I think, make it sound fancier. (why would you willingly add it more waffle and possibly stall the flow of through in speech?)

Monosyllabic nounTwo syllabic versionMeaning
(coek3)桌子(coek3 zi2)table
(fong4)房子house
(mou2)帽子hat
(tou3)1兔子rabbit
(tou5)1肚子tummy
(tou4)1桃子peach

Note

In this usage as soon as you’ve appended the original monosyllabic noun, there is (mostly) no need to add on the 子 suffix afterwards.

Footnotes

  1. I have noticed afterwards that I’ve included three words that only differ by their tones as consecutive examples. 2 3